When a voltage is applied, a 3-wire circuit acting as a potential divider provides either a voltage or a resistance that is linearly proportional to the travel of the probe and can thus be used by the test system to provide a distance measurement.
To take into account electrical and mechanical tolerances, the system needs to be calibrated to provide the exact plunger position. This can be achieved either by calculating the difference between to measurement values in relation to a reference position, or by using a special “golden device” as a reference.
Depending on the hardware and software of the test system, the measurement signal can be zeroed at user-defined positions. This method allows positive or negative deviations to be determined without the need to calculate the differences.
The sensor system has a measuring range from 0- to 5.2 mm, an accuracy of ±2% and a reproducibility of ±0.05 mm.